Call me hard to convince, but “Attack Iraq No” and “No Iraq War” sound like they came from the “Purple Monkey Dishwasher” school of sentence creation.
I mean, yes, these signs are cheaper to make than ones that say “Please don’t bomb the fuck out of Iraq,” and, yes, it’s arguably the show of support (or lack thereof) that matters, but are these slogans really that effective?
Optional homework: Write your own anti-war slogan.
Well, “I’m a craven little coward who’s afraid I’ll get drafted!” just doesn’t have quite the same ring to it, you know? Most of the ones I’ve seen on TV have been “No War For Oil” which is better than the ones you’ve mentioned. Of course, it seems like wars for oil are shorter than ones of ideology, religion, or territorial expansion, so…
here are some quasi-good ones. They have to rhyme so people will remember them.
No destruction for reelection (a remark on how Bush is supposedly using the war to unify the country behind him so he will win in 2004 & have something to brag about)
The army is to keep america safe, not for Bush to retaliate (a remark about how his dad failed to solve the Saddam problem, and about how Saddam tried to have his father killed)
You’d probably have to make some that question the principles behind the war too like
“if humanitarianism is important in this war, why aren’t we going into Myanmar”
“Israel has violated more UN resolutions than Iraq, but maybe they will help us attack”
calculus, you’re a fan of the Conan O’Brian sports fan guy, aren’t you? (You know, the one whose cheers go on for full minutes?) 
These are supposedly signs that were noted at a recent rally. A friend sent them by e-mail to me and I don’t know if they’re actual signs or just someone’s effort to be clever.
These colors don’t run the world.
One nation under surveillance.
How did our oil get under their sand?
Go Solar, not Ballistic.
Who would Jesus bomb?
Start Drafting SUV Drivers Now.
Don’t blame me, I voted with the majority.
Buck Fush!
It’s NUCLEAR, not NUCULAR, you idiot!
Patriots are idiots - Matriarchy Now!
Resistance is Fertile.
(Pictures of sheep carrying flags) Stop Mad Sheep
Disease Now.
(UFW sign) Pick Fruit, not Fights.
(On a five year old) More Candy Less War.
Say can you see my democracy?
(With pictures of Bush, Cheney and Rumsfeld) Asses
of Evil.
It’s the oil, stupid.
War is expensive, Peace is priceless.
Read between the Pipelines
No More BuShit.
Smart weapons, Dumb president.
The only thing we have to fear is Bush himself.
How many Lives per Gallon?
Peace Takes Brains
Anything War can do, Peace can do better.
Negotiation Not Annihilation.
Make touchdowns, not war - Go Raiders!
Another patriot for peace.
Oh Say can You Cease?
Star Spangled Bummer
Don’t Arm a Son of a Bush
Don’t do it George, Dad will still love you.
Power to the Peaceful
The last time we listened to a Bush, we wandered
in the desert for 40 years.
I’m sorry to say I don’t even know where that is.
:o
Myanmar used to known as Burma.
When I was protesting the Poll Tax in London in 1990, I made up the following slogan:
“You say poll tax,
I say boll-ax!”
Nobody used it. 
As for the war… I’ve been reading the SDMB too long to be able to come up with a trite summary. How about
“I’m dubious about the motives behind the war,
Though I don’t think that is a good enough reason
To oppose the removal of Saddam from power,
But I am also extremely concerned
About the inevitable civilian casualties
And the almost-certain high level of recruitment
To anti-Western terror groups
Throughout the Arab and Islamic worlds,
If this action goes ahead,
And I think pre-emption sets
A nasty precedent
For further US belligerence.
Yeah!”
Call this a wild guess if you like, but are you from the U S of A by any chance?
I’ve been wanting to make a bumper sticker that says “The good guys don’t start wars.”
A bas la Busherie (down with the Bu(t)shery)
Who let the bombs out? Bush! Blair! Chretien! (pause for groans)
They don’t seem any less creative or any more stupid than the reasons we’ve been given for going to war.
My school is littered with gaudy flyers cleverly urging “Don’t Invade Iraq!” I really don’t see how you can expect any slogan to top that.
… I smell a t-shirt … !
I personally think it’s having to pick the lesser of two evils: America, or Iraq. This war will come and go.
That’s why this is the best slogan, because it works for absolutely everything:
No!
A lot of the rallies around here are called “Not In Our Name” rallies and there are signs in windows that say the same thing.
Why test our weapons in the Midlle East when Florida has so many weirdos?
UN a bomber!
So he tried to kill your dad? Let it go…
I dunno . . . As a slogan, I can’t see how that beats the ole standard: “One, Two, Three, Four! We don’t want your fucking war!”
War is smelly. Let’s not.
Malacandra , Sock Munkey must not be from the United States. Anyone from the United States would have seen the Seinfeld episode where Elaine must go to Myanmar (Burma) to track down Peterman to approve an $8,000 hat that George bought on the Peterman account.
Co-stan-za!
